Electrical connector for tubes



July 11, 1944. MOLAUGHLIN I 2,353,348 ELECTRICAL CONNECTOR FOR TUBESFiled Aug, 5 19 inventor HenneTH m Lnusrmn Ohm-neg Patented July 11,1944 ELECTRICAL CONNECTOR FOR TUBES Kenneth McLaughlin, Summit, N.J.,assignor to Radio Corporation of America, a corporation of DelawareApplication August 5, 1942 Serial No. 497,528

6 Claims. 7 (01. 250-215) My invention relates to connectors forelectrical devices which have a plurality of leads projecting from theouter surface of a flattened member and more particularly to anelectrical connector or base for electrical discharge devices comprisinga tubular envelope having a flat disc stem or closure at one end with aplurality of closely spaced leads sealed in and projecting outwardlyfrom the stem.

Some electrical discharge devices, such as electron discharge tubes,have "a tubular envelope closed at one end by an end wall or disc stemin which a number of leads are sealed to project outwardly from the stemand, in general, longitudinally of the tube. Some tubes are about aninch long and approximately three eighths of an inch in diameter withfrom six to eight leads sealed into the stem, the leads being arrangedin a circle concentric with the center of the stem. The leads are spacedso close that it is not feasible to use a base of the conventional typenor to insert the projecting leads directly into a conventional socketbecause the live parts of such a base or socket would be too close forpractical purp ses.

The principal object of my invention is to provide for such a device ortube an electrical connector or base which is a longitudinal extensionof the tube no wider than the tube and which provides between the leadsand the external circuit contact points separated by distancesconsiderably greater than the spacing of the spacing of the leads at thestem. Another object is to provide such a connector which can beinserted if desired in a socket no wider than the tube so that the tubescan be mounted side by side with minimum clearance.

Still another object of my invention is to provide a connector by meansof which the leads can be separated and held with their outer endsspaced a safe distance apart to facilitate testing and other operationsduring the manufacture of the tube.

In accordance with my invention the connector or base comprises a sheetof insulation which is a longitudinal extension of the tube, andpreferably is a sheet set on edge on the end of the tube to projectvertically from the tube end, and of such size and shape that the leadsmay extend along the sides of the sheet base or connector with theirouter ends secured to the outer edge of the sheet base at safe distancesapart. The base may be permanently affixed to the tube if desired or itmay be used as a convenient means for suitably spacing and holdingtheleads during manufacturing operations or where the tubes arepermanently placed with the leads soldered to supply conductors.

My invention will best be understood in connection with the accompanyingdrawing in which, merely for purposes of illustration, my invention isshown applied to a miniature type of electron discharge tube having atubular envelope and a flat disc stem at one end, although the inventionis not restricted to tubes of this type and size.

In the accompanying drawing:

Figure 1 is a side view in elevation of an electron discharge devicehaving a base made of sheet insulation in accordance with my invention,and

Figure 2 is an end view of the tube shown in Figure 1 with the leadsextending along opposite sides of the sheet base with their outer endssecured in notches in the outer edge of the base.

The particular type of tube shown comprises a tubular shell or bulb l3,preferably of metal, with a flat lower end formed by a flat disc stem IIof glass in which there are a number of leads l2 arranged on the stem ina circle concentric with the stem. In the particular tube shown, thereare eight leads uniformly spaced, and since the stem is only aboutthree-eighths of an inch in diameter, the spacing between the leads issmall. The leads extend outwardly from the stem and at the time the baseis applied to the tube are preferably one or two inches long.

In accordance with my invention the connector or base I3 is made of asheet of insulation, no greater in thickness than the spacing betweentwo adjacent leads l2. This sheet of insulation preferably fiber, highgrade cardboard, or other well-known sheet insulation, is set on the endof the tube edge-on to extend diametrically across the stem and toproject vertically from the tem in substantially the plane of thelongitudinal axis of the tube. The base preferably comprises a verticalsemi-circular wing section l4 longer than the diameter of the base, andhas in its straight upper edge a recess l5 of such a size that it fitssnugly over the lower end of the bulb l0 containing the stem II.

The leads l2 projecting outwardly from the stern lie along the sides ofthe base l3, as best shown in Figure 1, and extend in a generally radialdirection to the outer edge of the wing 14. The leads may be drawnfairly tight and spaced evenly along the wing, with their outer endssecured to the wing, preferably by doubling or hooking them over theedge of the wing, thereby holding the base on the tube firmly enough formost purposes. If desired, the base may be permanently aflixed to thetube by cement or adhesive that ticks to the glass stem and to the base.The outer end of the leads are spaced along the outer edge of the wing,preferably by means of spaced notches [6 in the outer edge of the wingso that the separation of the outer ends of the leads l2 along the outeredge of the wing section is great enough to prevent short circuits andleakage. The leads may be secured to the base l3 in any convenient way,preferably by forming the outer ends of the leads into hooks H which fitinto the notches 16. It is obvious that the outer ends of one or more ofthe leads may in addition he provided with some form of contact membersecured to the base and joined to the end lead. Where the base ispermanently secured to the tube, such contacts may facilitate the makingof good connections with a suitable socket.

A base or connector constructed in accordance with my invention isuseful during the manufacture of the tube in facilitating separation andholding of the leads during testing and other manufacturing operations.After testing and similar operations requiring electrical connections tothe leads have been completed, the base 13 may be removed by unhookingthe outer ends of the leads from the edge of the wing I4, thus leavingthe leads free for whatever other operations may be required. In somecases, where eight leads are arranged in a circle and project from astem, some of the leads may be idle and may be cut on so that in thefinished tube only a part of the leads are utilized; for example, insome types of tubes eight leads are utilized during manufacture but onlyfour leads are needed after the tube has been completed. In such case mybase provides a convenient way of handling the tube with ease and safetyduring the manufacturing operations.

While the base is on the tube, part of the leads are distributed alongone side of the base and the remainder along the other side; forexample, as shown in the drawing four of the eight leads extend alongone side of the sheet base and four along the other side, the outer endsof the alternate leads being hooked into successive notches so that amaximum separation of the leads during the handling and operation of thetube is obtained.

I claim:

1. An electrical connector for an electrical device having an envelopewith an end wall and a plurality of leads sealed in and extendingoutwardly from said end wall, comprising a sheet of insulation afiixedto and abutting edge-on against said end wall and projecting verticallyfrom said end wall, said leads extending along side and secured in placeon said sheet with portions remote from said end wall spaced a distancegreater than the spacing between said leads at said end wall.

2. An electrical connector for an electrical device having an envelopeand a plurality of leads extending outwardly from and spaced in a circleon one end of said envelope, comprising a sheet of insulation no thickerthan the spacing between adjacent leads and set on edge directly acrosssaid end and abutting edge-on against said end, said sheet fittingbetween the leads of two diametrically opposite pairs of leads andprojecting beyond the periphery of and perpendicular to said end andhaving spaced notches in its free edge, said leads extending along sidesaid sheet and hooked at their ends into said notches.

3. An electrical discharge device comprising a bulb having an end Walland a plurality of leads sealed in and projecting outwardly from saidend wall, a sheet of insulation abutting edge-on against said end wallbetween pairs of said leads and having an integral wing projectingvertically from said end wall, and means for aifixing the ends of saidleads to said wing at points spaced from said end wall, said pointsspaced from said end wall, said points being spaced along said wing atdistances greater than the spacing between said leads at said end wall,some of said leads extending along one side of said sheet and theremainder extending along the other side thereof.

4. An electrical connector for an electrical device having an envelopewith a flat end and a plurality of spaced leads sealed in and extendingoutwardly from said end, comprising a sheet of insulation thinner thanthe spacing between diametrically opposite pairs of leads and longerthan the diameter of said flat end, said sheet extending across andperpendicular to said end with its inner edge resting on said flat endand having in its outer edge notches spaced more widely than said leadsat said end, with alternate leads extending along opposite sides of saidsheet, the outer ends of said leads being secured in successive notches.

5. An electrical discharge device comprising a tubular bulb having atone end a flat stem with a plurality of leads sealed in said stem in acircle and projecting outwardly from said stem, a planar base comprisinga sheet of insulation thinner than the spacing between leads in saidstem, said sheet being semi-circular and affixed to said stem with theflat edge of said base abutting edge-on against said stem and positionedto extend diametrically across said stem between opposite pairs ofleads, said fiat edge having a notch near the middle fitted over the endof said envelope, said base having notches spaced along its curved edgeat distances greater than the spacing between the leads in said stem,said leads extending radially outwardly from said stem along oppositesides of said semi-circular base with the outer ends of said leadshooked into said notches.

6. An electrical connector for an electrical device having an envelopewith a flat end wall and a plurality of leads sealed in and extendingoutwardly from said end wall, comprising a sheet of insulation aflixedto and abutting edge-on against said end wall and projecting verticallyfrom said end wall, said leads extending along side and secured in placeon said sheet with their outer ends spaced a distance greater than thespacing between said leads at said end wall.

' KENNETH McLAUGHLIN.

